code: def learn(self):
      batch_data = self.dataset.get_batch(self.config["batch_size"])
      loss = self.alg.learn(*batch_data)
      loss = loss.detach().cpu().item()
      return loss
  
file_path: PARL/benchmark/torch/DT/agent.py
imports: import parl
  import torch
  import numpy
  from data_loader import DataLoader
label_desc: Use image node_id 3 for calling the DTAgent obj's underlying member method code with example usage: obj.learn() and returns: loss